Three Pesky Comma Errors

When writers use commas correctly, they help readers make sense of text. However, when commas are not used correctly, readers may have to ponder over a sentence to understand its meaning. This causes the reader to think about the writing instead of the message being delivered, which is always a sign of poor writing. At Precise Edit, we see the same three comma errors repeatedly, so we offer the assistance below to help you improve your own writing.

Problem One: Comma before conjunctions that join two independent clauses
First, let's define the terms. In this case, the term conjunction refers to the coordinating conjunctions for, and, nor, but, or, yet, so. (Some people use the acronym FANBOYS to recall this list of coordinating conjunctions.) The term independent clause refers to a complete sentence, whether it stands alone or is part of a longer sentence. Basically, if the independent clause were to start with a capital letter and end with a period, you would read it and say, "Yup, that's a complete sentence." Now let's examine an example using this rule correctly.

I saw her, and I smiled.
Both I saw her and I smiled are independent clauses. All you need to do is add punctuation, and they would be complete sentences. These two sentences are joined by the conjunction and. According to this rule, a comma should be placed in front of the conjunction. Sure enough, the comma is there. (We did say that this is a correct example.) You might be thinking, "Yeah, but if you leave out that comma, I will still understand what the sentence is about." Well, that was a simple example. Let's look at a couple of others that are a bit more complicated.

She looked at me, and Bob, under the tree, sighed.If you leave out the comma before and, the reader will have to decide whether she looked at only me or if she looked at me and Bob. Only when you reach the end of the sentence can you determine that she is looking at me and that Bob is the person sighing.

Bob saw her looking at me, so wistfully he walked away.
If you leave out the comma before so, the reader might think that she is looking at me so wistfully. Instead, Bob is the wistful one. Without that comma, the reader might unconsciously correct the sentence this way:
Bob saw her looking at me so wistfully. He walked away.
In doing so, the reader fixes your punctuation incorrectly and has an incorrect understanding of what you are trying to communicate.

Be careful with this rule. Sometimes what looks like an independent clause might only be a phrase with an implied that. For example:
I knew that she loved me and she always would.
The phrase she always would looks like an independent clause, but it isn't. It is actually an abbreviated form of that she always would. The complete sentence is I knew that she loved me and that she always would. This doesn't require a comma according to the rule.

Problem Two: Comma after every item in a series (not including the last item)
First, let's define our terms. By series we mean a list. For example:
She saw me, Bob, and Tom glaring at each other.See that comma before and? It is referred to as the serial comma, or, for our British friends, the Oxford comma. That's the comma many writers leave out. To be quite honest, some editors say that comma is not necessary. After all, they say, the commas in the list are filling in for the word and, and since the and is already there, adding the comma is redundant. Why, then, do we say that you should add it?

Here's the reason. Our first task as editors is to improve reader understanding. Sometimes items in lists are complicated and comprise two or more other items. Without that comma, the reader may have difficulty understanding how the items are grouped. For example:
Mary saw me, Bob and Tom, and Frank walking in her direction with amorous looks in our eyes.
With the comma after Tom the reader knows that Bob and Tom are walking together and that Frank and I are walking alone. Without the comma, the sentence is still correct, though clumsy, but it conveys a different meaning. The sentence
Mary saw me, Bob and Tom and Frank walking in her direction with amorous looks in our eyes
no longer tells the reader that Bob and Tom are together or that Frank and I are walking alone.

Based on the previous example, you might be thinking that you should simply add the comma when it improves understanding but that you don't need it otherwise. Since we believe that punctuation use should be consistent (i.e., not changing from sentence to sentence), we always add that comma.

Problem Three: Comma after introductory subordinate phrases
First, let's define our terms. A subordinate phrase is a phrase that begins with a subordinating conjunction (e.g., since, when, although, as). These phrases are not independent clauses (think: complete sentence) because of that subordinating conjunction. They must be attached to an independent clause. Subordinate phrases tell when the main action occurred, provide a condition for it to occur, give opposing information about the action, or show cause and effect. (We have another article about subordinating conjunctions that you may wish to read if this is confusing.) For example,
Since she did not like any of us
is a subordinate phrase. If you were to take away the subordinating conjunction since, you would have an independent clause, but with that conjunction, the phrase can no longer exist alone (at least not correctly). The other term, introductory, is easy to understand. It means at the beginning of the sentence. Now let's examine an example using this rule correctly.

Although we were besotted with love, we knew that our quest for her affection was pointless.
(Note to our young adult readers: that's life.) The phrase Although we were besotted with love is a subordinate phrase giving opposing information about the main action knew, and it is at the beginning of the sentence. Thus, it needs to be followed by a comma.

Like the previous rule, some people agree with it, and others think it is only necessary when the introductory subordinate phrase is longer than some arbitrary number of words. For example, some people say to use this comma when the phrase is five or more words. However, like the reason why we always use the serial comma, we prefer to be consistent. You will need to make your own decision on this. Because this rule can be a bit confusing, we're providing a few more examples.

As he ran away from Mary, Tom fell and skinned his knee.
Although his knee hurt, the pain in his heart consumed his attention.
Because his affections had been crushed by Mary's indifference, Frank gave up on her and called Susan instead.
If Susan was not home, he would call Clara.

Here's an example of a sentence that would be confusing without that comma:
While Susan did not want him, calling her seemed like a good idea.
Without the comma, the reader will read
While Susan did not want him calling her...
which will make sense until the reader gets to seemed like a good idea.

Some people think the editors at Precise Edit are too picky. We like to think of ourselves as "detail oriented." That sounds better, right? Really, though, we are simply trying to improve reader understanding and writer professionalism. Applying the rules above will help you do the same.

When you are ready for expert assistance with your writing, contact Precise Edit.